Meurer and team used Amazon Mechanical Turk to crowdsource 1,000 survey participants age 18 and older who met Amazon’s vetting requirements as a performer of human intelligence tasks. Participants were given $1 for completing the survey.
Respondents were asked to imagine themselves in two hypothetical situations for diagnostic testing: low-risk chest pain and minor traumatic brain injury.
Participants were given the three variables of benefit, risk and cost along with four values for each in both scenarios.
“We defined the benefit as the chance that the patient had a true-positive finding. The risk was defined as the chance of developing cancer within the next 10 years due to the radiation. And the cost was an additional out-of-pocket expense for the test,” Meurer says.
The researchers used the values of 0.1, 1, 5 and 10 percent for the benefit and risk variables and $0, $100, $500 and $1,000 for the cost. They randomly distributed the values among the respondents.
The research team also collected demographics on participants, such as age, gender and history of medical conditions.
Using multivariable logistic regression models, the researchers found that participants who accepted a diagnostic test increased from 28.4 to 53.1 percent when the benefit increased from 0.1 to 10 percent.
When the risk from the test increased from 0.1 to 10 percent, participants who accepted a diagnostic test decreased from 52.5 to 28.5 percent.
Finally, when the cost increased from $0 to $1,000, the researchers saw the largest change in participants agreeing to the test, decreasing from 61.1 to 21.4 percent.
The research team noted cost appeared to be the most influencing factor in the study.
“We found that participants were more apt to get the diagnostic test if it was at a lesser cost,” Meurer says. “It proved to us that people are potentially sensitive to getting an additional bill for diagnostic testing.”
“In addition, if participants saw their chance of getting a disease was incredibly rare, they felt the sense that ‘I might not have this disease, so I’m not willing to spend extra on it because there’s not as much risk.’ When the risk exceeded the benefit, the number of participants interested went down at a remarkable rate.”
Researchers note limitations to the study. Mainly, those taking the survey were in a hypothetical situation and not seeking medical care. Care in an emergency department, as a contrast, can be stressful and influence decision-making.